Thanks onasled, you finished my thoughts & said it better than I did.

 

I don't get it. If the color represents the amount of deformation (aka scale):
(from the initial post)
and the color does not mean the same thing in both pictures, then the scale (color) as presented is not the same.
color = scale color1 <> color2 therefore, scale1 <> scale2
QED.


Quote from post #88, beginning of paragraph 2:
The title of the thread is "M7 SRP = No Mushrooms". Can we agree that the title is not the same as "the SRP appears to give measurable resistance to deformation"? The latter is not as concise, but more accurate.

 

Still getting this thread in my emails and I just have to remark in the event that you do not realize how you sound and why it would put anyone on the defensive. In your statement above you say you are in no way trying to attack them then procede to do just that with words like "weak" "disgrace", etc and even your first post began with the clearly negative "That write-up is really not convincing at all to me." followed by what reads like a loaded point by point criticism of the vendor post vs simply asking questions. Then other statements like "That write-up as it is above is just a bunch of pictures." follow and that tone, also in other people's posts, is what sets the stage for the defensiveness and mess of posts that came after.

Perhaps you are not aware of how it comes off and why things followed as they did, so I can only tell you that to a third party like me it seemed overtly aggressive so I can only imagine how it would feel to have those comments, among others, directed at me and how it would make for a defensive reaction.

Anyway, the plates sound interesting and fall into the better safe then sorry category for me and I'll consider getting them. The fact is BMW has had weak suspension component and subframe issues for a long time on many cars and any sort of reinforcement to the rear shock mounts (and apparently some on the front too) and subframe has always been advised. Since those are RWD and the MINI is FWD and has different dynamics I'm not surprised that the front towers might require something extra to help protect their integrity - and it considering everything it might be a good idea to cover the RSMs too, esp if you have stiffer suspension, bigger wheels/less sidewall, bad roads or any autoX putting extra stress on it.

I'd agree that perhaps M7 should change the title of the thread and be careful of what is promised with their product if just to cover their butts liability-wise since there can be extreme circumstances that override the reasonable protection provided by the plates.

 

Looking at pictures of mushrooming in various degrees, it seems to me more that the effect is of the inside bolt, the one towards the engine, is pushed up first. The lower control arm would sort of dictate that this would occur being that it constrains the lower area and would draw it inward as it swings up. Just a theory based on pictures and the geometry. After the initial deformation of the inside section of the sheet metal, the car would settle back to running straight, but the suspension would be strained. Rather than drawing the stretched metal back down, the unstretched outer metal would then follow the deformation and you'd have mushrooming around the entire surface. In this case, the SRP would resist the initial deformation on the inside section, and also resist the stretching of the sheet metal over the entire surface.

Basically the SRP is attemtping to hold the position of the bolts in place, which would not allow the metal within the bolt triangle to stretch. It would also distribute the force over more area, so more force would be required for deformation.

At least that's another theory to add to the pot. The simulated force is an impact primarily straight up, with a slight bias towards the inside.

 

The color scale is specific to each image. IE even though the deformation is less with the SRP image, the red would indicate the maximum deformation in reference to that image only and is not equivalent to the red deformation in the unequipped simulation. For a direct 1:1 comparison, use the uncolored images of the defomation. The colored images were meant only to allow an easier visualization of the specific deformation for each case.

 

I think the issue of visualization is in the exaggeration on the deformation. It's likely that the corner of the plate would lift slightly, however the computer did not calculate much deformation in the situation. That corner was not moved from it's original position, so in exaggerating the effect, it seems to be stuck to the strut tower, since there was also no deformation of that corner of the strut tower. An unfortunate side effect, it seems.

However, it is possible that the SRP would bend, since the force would be serving to pull apart the plate at the holes. This would stretch the metal inbetween, and it's a possible scenario that it would cause bending in this case.

 

Will thanks for taking the time to address my concern. I too thought of the effect of the bolts displacing in relation to each other, and think the plate will indeed help with that. The next thing to happen then is for one of the bolts to shear. I have seen this many times. However that in itself may help with protecting the strut tower....Not sure.
Again, I think theory will be proven or disproven in the real world. Only there will be a lot of variables to sort through then.

 

I guess that makes sense. Please correct me if I'm wrong. My game plan is to get the SRP plates and if the one on the right side doesn't fit flush with the top of the strut tower, use a BFH and 2x4 on the top of the strut tower until the SRP does fit flush.

 

I

 

Sounds like you are with the program. The BFH should do the trick but if need be do not hold back from breaking out the VBFH is the situation calls for it.

Randy
M7 Tuning

 

 

Why doesn't someone volunteer their MINI (with SRPs installed) and hit a big pothole at high-speed for us? That should answer the question as to whether they work or not as advertised.

Actually, I'm thinking to order these for my new MCS when it comes, as my commute has quite a bit of potholes along it (e.g. La Cienega / Fairfax in Los Angeles). Better safe than sorry, IMHO...

BTW, if the SRP-integrated strut brace uses a fixed (not hinged) connection, it should help absorb the force of an impact due to the cantilever nature of the connection (e.g. think of a metal ruler sandwiched under a book sticking out from the side of a desk -- if you hit the tip of the ruler, it will resist bending as best it can...). Not sure if this is how M7's new strut brace is designed, but maybe you guys want to think about for SRP v2?

 

Peter,

I was simply making a generalization which applies to business as well as personal life. I did not intend to disparage your company nor any vendor for that matter. I have found that the rule works well in personal life as well as business. If you READ my post I did not even remotely imply that Dinan nor Webb Motorsports were a source for a SRP-like product. As far as I know I don't think either company sells one. I was, however,trying to make the point that IMO they are very careful about not making claims that they can't deliver on and are good business models. On another note, I have never kissed up to any MINI vendor and I resent any reference that I have. I have never puchased anything from Dinan and only a Milltek exhaust from Webb. I try to do my homework and buy the best products that are available. My next purchase will probably be the M7 oil-catch can. I prefer it over the Alta product. Please try to stay calm.

 

Regarding the SRPs as is... I think they will help, because their distributing the force of the impact to more than just the default strut tower. However, as others have pointed out, the weak point will be in that they are only connected using the 3 bolts -- all deformation loads will be transmitted through them (i.e. they are what's keeping the plate "stuck" to the strut tower).

For a minor impact, I think it might help. However, if you hit something pretty hard, my guess is you'll strip the bolts (to some extent) and possibly have some 'shrooming on the shock tower.

In regards to Will's model, maybe you want to run the analysis with the SRP and strut towers only connected at the locations where the bolts are? That might be more representative than assuming that they're "glued together" in the FEM analysis. (If you already modeled 'em that way, just ignore my comment.)

 

Or just 'glue' them together? There are some righteous industrial adhesives out there (Lotus Elise chassis anyone?), and it might be an upgrade kit that M7 can offer. A little more protection for a little more cost?

Don't worry about me, I'm already sold. Just thinking with my fingers

 

The glue might be super strong, but then there's a good chance that the paint would come off. But, it depends... spread over a lot of surface area, it might hold.

 

There are in fact adhesives that are designed specificaly to bond metal to metal.{we use it all the time in autobody repair} This I think would be a benefit to helping the srp absorb more of the impact, than simply being attached by the strut bolts.
This would still be for small to medium impacts, which is what the srp was designed for.
Now I know what you are thinking, but some of these adhesive are designed to release with the use of heat usually around 350 degrees. Higher than underhood temperatures but low enough that this temperature can be created with a heat soarce that is readily available & won't hurt surrounding paint.
These adhesives are available at local auto supply stores & are easy to apply.
Will, do you think this may be worth some testing.

 

The paint would have to be removed in the area that the boding material is to be applied. There is a special primer that has to be applied{using a small brush} and then the bonding material. This is a metal to metal adhesive. There is usually a 1/2 hour working time and an overnight cure time.

 

I have not followed the entire thread. I checked the M7 webbsite and saw that this anti-mushrooming device appears to fit on top of the strut tower, not both on top and underneath it. If each strut tower were sandwiched between and upper and lower reinforcement plate, I suspect that the top of the tower would be less likely to deform.

If there were only one plate used, I suspect having a reinforcement plate under the strut tower would work better to prevent deformation. The major shock is in an upward direction, and occurs when a sudden impulse (pothole) jams the strut upward.

I have the Webb Camber Plates which as you know are pretty thick and go under the strut tower. I believe they work well at spreading the impact of the shock/spring over the entire area of the strut tower. The downside of course is that the Webb camber plates do raise up the front of the car a little.

I suspect a heavy duty camber plate which fits under the strut tower would compliment or substitute for the top only reinforcement plate, if that is in fact whaat the M7 device is. But like I said, I'm not sure if that is what the device is or not.

 

It's an interesting concept. My feeling is that you would gain strength equal to the bond created, since if overstressed the bond would release. I'm not familiar with the adhesives, so I can't comment on the strength, but perhaps you could? The simulation was run with the only bonded points being the three bolts.

 

The rivits on the wings are just to make old people feel safe! Some of the adhesives are stronger than you would believe, and because they bond over a larger area, they do more than a couple of bolts can. But that aint no bolt on....

And Will, don't worry about the flamers. There are a few in every group.

Matt

 

Awesome vid as usual How did your tower hold up after that big ouch on the right sweeper?

 

The Lotus Elise's chassis is also glued together

 

M7;
I'd rather get the complete strut tower bar than just the SRP's. Will there be any fitment issues with the following: KW Variant 2 and RDR camber plates.

Also does the bar have clearance for K&N intake and the Unichip.

Seann

 

That's very true, but I'm not sure how easy it is to get ahold of those glues. Any ideas? I don't know any airplane builders...hehe.

But I'm almost willing to try it, for science!

Thanks, Matt.